Equol (4`,7-isoflavandiol) is an isoflavandiol metabolized from daidzein, a type of isoflavone, by bacterial flora in the intestines. While endogenous estrogenic hormones such as estradiol are steroids, equol is a nonsteroidal estrogen. However, only about 30-50% of people have intestinal bacteria that make equol. Equol may have beneficial effect....